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Re: A question about numerically solving differential equations

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  • Subject: [mg130308] Re: A question about numerically solving differential equations
  • From: debguy <johnandsara2 at cox.net>
  • Date: Tue, 2 Apr 2013 03:26:48 -0400 (EDT)
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  • References: <kirks3$at8$1@smc.vnet.net> <kjb43b$8jm$1@smc.vnet.net>

2 D[f0[r], r]/r + D[f0[r], r, r] == -2 A f1[r]/r^4 +  2 A D[f1[r], r]/
r^3
-2 f1[r]/r^2 + 2 D[f1[r], r]/r + D[f1[r], r, r] == 2 A D[f0[r], r]/
r^3

I tried it later.  I cannot get anything
          y`[x]==g`[x]==y[x]==g[x]
to work using any conditions i try.

NDSOlve[{ y`[x]==g[x], g`[x]==g[x]+y[x], g[1]=1, y[1]=1 },{y,g},{x,
1,2} ]  (* foo *)

Is the only form I can get to work using two funs.  Which is what the
book example uses.

I'm unsure how to re-express your eq'n that way to try it.



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